Names an attribute of a noun and adds additional meaning to it.
Adjectives modify the noun that directly follow them. Every adjective is either a い-adjective or な-adjective.
All adjective can be categorized as either:
As mentioned, most adjectives that end with い are い-adjectives and can be used to prefix a noun directly to modify it:
This class of adjectives act very similarly to nouns, but can also be used to modify a noun using the following rule:
They can also be conjugated into the negative, past and past negative using the same rules that apply to nouns:
There is just one exception to the above conjugation rules, which is いい. It originates from 良い and uses all of its conjugations. Since this word is quite common, it's best to remember it and the corresponding conjugation table.
Furthermore, the word かっこいい is also derived from いい, meaning that it uses the same conjugation patterns.
And some examples: